Orthogonal frequency-division multiplexing (OFDM) offers a robust multicarrier modulation technique in optical communications to meet rapidly increasing bandwidth demands. High speed data transmissions may be carried over many lower rate subcarriers across a transmission channel. During transmission, the OFDM signal becomes distorted due to a combination of channel effects that a receiver must be able to estimate in order to mitigate the distortion. Special data symbols may be used in OFDM symbols to assist receivers in performing this channel estimation during signal reconstruction, such as training symbols, preambles, and pilot subcarriers. These special data symbols are predetermined signals known by the receiver, and consequently assist in channel estimation. However, the bandwidth consumed by these special data symbols is a reduction in bandwidth available for customer data.